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Neutrino Factories and Muon Colliders. Leo Jenner. Overview. Physics motivation Size and layout Neutrino factory -> Muon Collider Collaboration UK effort Opportunities ISS CDR: http://www.hep.ph.ic.ac.uk/iss/reports/ISS-AcceleratorWG-final.pdf. ‘Why does the universe exist?’.
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Neutrino Factories and Muon Colliders Leo Jenner
Overview • Physics motivation • Size and layout • Neutrino factory -> Muon Collider • Collaboration • UK effort • Opportunities • ISS CDR: http://www.hep.ph.ic.ac.uk/iss/reports/ISS-AcceleratorWG-final.pdf
‘Why does the universe exist?’ • Only exotic theories incorporate a big bang with unequal particles, anti-particles and photons at beginning of universe • Today nB/nγ ≈ 6x10-10 • Muchannihilation in early universe, but not perfect • CP-violation provides a possible solution: observed CP-violation in quark sector only makes one galaxy… • CP-violation of heavy Majorana neutrinos could provide the answer • Recent discoveries have caused excitement: oscillations mean mass • Study of neutrinos can give information about extremely high energies via the See-saw mechanism • nν/nγ ≈ 1/3
How big would a neutrino factory / muon collider be? ILC VLHC or RAL? 73km CLIC
Muon beams make neutrino beams • mμ/me = 207 • beamstrahlung, bremstrahlung, initial state radiation considerably lower • low energy spread: dp/p=0.003% which gives scanning precision (A0 , H0) • But muon lifetime: 2.2 microseconds • rapid acceleration and cooling required • 4 MW 10 GeV proton beam gives required 10^21 muons / year
FETS RFQ FETS chopper Beam Fast chopping section Slow chopper and beam dump FFAG II (8-20GeV) Gran Sasso, Soudan Mine, Boulby, Homestake, Kamioka... RF cavities create bunching in the beam Bunch rotator reduces energy spread by rotating bunch in longitudinal phase space Ionisation Cooling: Liquid H2 absorber, see MICE
Low energy muon physics • Neutrino Physics • Energy frontier collider (1.5 – 4 TeV)
UK MICE Collaboration Argonne BNL Budker CERN Columbia Cornell DL DESY Fermilab IIT Imperial INFN Indiana JINR Jlab Karlsruhe KEK Lancaster LBNL Michigan State Mississippi Northern Illinois Oak Ridge Osaka Oxford Pohang Princeton RAL Tel Aviv Triumf UC-Berkeley UC-Los Angeles UC-Riverside University of Chicago
UK involvement / Synergies • Proton driver front end test stand • beam chopping, RFQ • Ifmif, subcritical reactors, ISIS • Solid target R&D • 1MW 2000°C thermal shocks • MICE • ε┴ ~ 7 mm , 1000X more in each transverse dimension, » 10X in longitudinal for muon collider • EMMA • FFAGs, medical applications
MICE in 200 MeV muon beam at RAL • Design, build, commission & operate realistic section of cooling channel • SciFi tracker already has Liverpool engineering effort • Measure performance in variety of operating modes & beam conditions • Results will inform the NF CDR Engineering is challenging
MICE assembled in steps I & II characterise beam III control systematics IV demonstrate cooling V cooling + re-acceleration VI full lattice section PHASE I Q4/07 Q2/08 PHASE II Q1/09 Q3/09 Q1/10 • Beam transport tuneable 140 – 240 MeV/c • Lead diffuser emittances of 2, 6, 10 (p) mm-rad • Aim is 600 muons / 1 msec ‘spill’ @ 1Hz through MICE • Extensively studied with linear optics codes + GEANT4 simulations
Test stand at Daresbury (under construction) to commission parts of RF amplifier system First MuCOOL 201 MHz cavity (LBL & JLAB) Successfully tested at Fermilab 16 MV/m after 5 days conditioning
Master Oscillator Controls etc Los Alamos CERN HT Supplies 300 kW Amplifier 300 kW Amplifier 300 kW Amplifier 300 kW Amplifier 2 MW Amplifier 2 MW Amplifier 2 MW Amplifier 2 MW Amplifier HT Supplies LBNL ASTeC 201 MHz Cavity Module 201 MHz Cavity Module RF LAYOUT
EMMA • Non-scaling FFAG • Many technical issues poorly understood • Prototype is best way forward • See Maxim’s talk • ( Joel , David )
Conclusions • Science program appears to be favoured by STFC – medium/long term experiment • Small footprint – no new facility required • Much R&D taking place now – many challenges remaining • Good deal of UK involvement
Science Case **** • Technical Issues and Challenges **** • Scale of UK support **** • Involvement Opportunities ****